Who has the most elite fighting force. Not nation like SAS OR Deltar forces?

SAS without a doubt, followed only by the SBS (sea bound brother of the SAS) and australian SAS. you will of course get plenty of americans saying that navy seals or delta are as good but the only reason they are decent is because they are trained by the SAS. in fact the americans requested that the SAS rescue american hostages in iraq (funny how they didnt ask delta instead). royal marines are probably the best infantry in the world, but the SAS are on a whole new level. joining them requires a 10 day torture exercise and apparently only 4 out of every 1000 applicants get in. SAS also have more experience than other elite units. they were invloved in afghanistan, iraq, first gulf war, the falklands, northern ireland and sierra leone. the iranian emby siege is still used to teach special forces across the world how to ault a building. other SF may come close but no unit has yet proved themselves to be better.